t = int(input())
if t >= 30:
  print('Yes')
else:
  print('No') t = int(input()) t int(input()) int input() input if t >= 30:
  print('Yes')
else:
  print('No') t >= 30 t 30 print('Yes') print 'Yes' print('No') print 'No' t = int(input()) int(input()) t
t = int(input())
if t >= 30:
  print('Yes')
else:
  print('No')